Cisapride acts directly as a selective agonist of serotonin 5-HT4 receptor with IC50 value of 0.483 μM. And It also acts indirectly as a parasympathomimetic.
Velusetrag(TD-5108)is an effective, selective, and highly potent agonist of the 5-HT4 receptor, and being developed for the treatment of gastroparesis, chronic constipation, and irritable bowel syndrome.